I recently took apart three external hard drives to retrieve their bare drives within to use in an internal application. In all three cases, there were no externally accessible fasteners to help with disassembly. I had to pop plastic clips loose, breaking some of them. For laughs, I thought it'd be fun to talk about a time when I had the opposite problem: I was confronted with far too many screws, most of which weren't relevant to the goal.

I have a NVIDIA GTX 1070 GPU and it had been in service for several years. NVIDIA designed the cooling shroud with a faceted polygonal design. Part of it was a clear window where I could see dust had accumulated through years of use. I thought I should clean that up, but it wasn't obvious to me which of the many visible screws held the dust cover in place. The visual answer is in this picture:

In case these words are separated from the illustrative image, here is the text description:

Starting from the clear window, we see four fasteners closest to them. These four fasteners hold the clear plastic to the dust cover and not useful right now. We need to look a little bit further. There are two screws further away between the clear window and the fan. Those are two of the four dust cover screws. The remaining two are on the top and bottom of the card, closer to the metal video connector backplate. Once these four screws are removed, the dust cover can slide sideways (towards the backplate) approximately 1cm and then the dust cover can lift free. After that, the four screws holding the clear window can be removed to separate the window from the rest of the dust cover.

In the course of discovering this information, I had mistakenly removed a few other screws that turned out to be irrelevant. Since they're not useful to the task at hand, I put them back without digging deeper into their actual roles.